Self-assembling polymers: The future of the hard drive?

When you think of increased storage capacity, you most likely don’t think of self-assembling polymers that only require heat in order to rearrange themselves. However, with the potential to increase HDD storage capacity fivefold, researchers at the University of Texas might make self-assembling polymers the norm.

Currently, information is stored by printing zeroes and ones as magnetic dots on a metal surface, with the amount of information able to be stored being relative to the spacing of the dots. The closer the dots, the more information can be stored. With current technology, the dots have become so close together that any decrease in the spacing between them would cause instability due to the neighbouring dots’ magnetic fields. However, if there was a way to protect the dots from neighbouring magnetic fields, they could be moved even closer together, creating more storage space.

University of Texas chemists and engineers teamed up to apply a coat of a substance known as a block copolymer – a grouping of polymers made out of more than one bondable molecule – to a metal surface. If delicately coaxed, such as with a bit of heat, the block copolymers are able to reorganise themselves into a regular pattern.

If a surface contains some kind of guide, the block copolymers can follow it. It just so happens that the magnetic dots on a hard drive provide the perfect guide for the block copolymers, and the copolymers provide just enough shielding from magnetic fields, thus being able to push the dots much closer together than the normal spacing, and without any worry of data corruption.

Up until now, the process – known as directed self-assembly – was only able to double storage space. However, C. Grant Wilson, professor of chemistry and biochemistry at the College of Natural Sciences, co-author of the study Christopher Ellison, and a group of students, have refined the process enough to the point that they’ve created block copolymers that rearrange into the smallest dots yet.

On top of that, the team also managed to set a record for how fast the polymers form into the correct patterns, which clocks in at around thirty seconds.

Though the polymers can reassemble fairly quickly, as well as follow the hard drive’s natural guide, orientation of the dots was still an issue. However, the team was able to create a special top coat to help the polymer form using a proper orientation, and it’s simply activated with a bit of heat. Because of this, the polymers are able to orient themselves in smaller patterns, which in turn allows for more storage space.

The tech is quite interesting, and not actually too difficult to understand, but a question one might wonder is if this new process will actually strike a chord with the consumer market. SSDs seem to be the wave of the storage future – or at the very least, the current trend – and more consumers are opting for the speed that comes with SSDs rather than the higher storage capacity of HDDs, regardless of the significantly lower gigabytes-per-pound cost ratio.

At some point, though, if the copolymer process can be brought to consumer production, that 2TB HDD could quickly become a 10TB HDD for a similar price, and then the choice between an SSD or an HDD will become even more difficult. You could have all the storage space you could ever need, or opt for speedier load times and deal with, for example, uninstalling a game to save space after you’ve beaten it.

At this stage, the team is working with HGST, a subsidiary of Western Digital, to see if the process can be applied to consumer product manufacturing. Hopefully they’ll figure it out soon enough, and we’ll all have to make the choice between a speedy SSD or an HDD with much more storage capacity than we know what to do with.